The path of least resistance

[galacticmonkey 5,000+ posts]

So the simple answer is that current doesn't just take the path of least resistance?

Exactly. If you run a 1/0 wire and a 4ga wire they will both be having amperage fed through them. Its just less resistance.

 

[91Chevy 10+ year member]

It doesn't take a SINGLE path, per say. But as I was trying to say. If you have an 1/0AWG wire, going from point A to point B, it has X-Ohms of resistance. If you have 2 runs of 1/0AWG wire, you have double the amount of conductor, therefore halving (theoretically, not literally) the amount of resistance, leaving you with 0.5X-Ohms. Those aren't practical real-world numbers, I'm just trying to explain it as well as I can.

 

[DNick454 10+ year member]

One thing you're forgetting is that wires gain heat as electrical current flows through them. Lets say the majority of the current is going through wire 1. Well wire 1 is going to heat up more, now wire 2 has less resistance and current flows through it. In high demand, high current, competition setups, the wires will equalize in a sense and there will be current flowing through both. Multiple runs of wire won't make a huge difference, but it's not completely useless if that's what you're wondering... hope this helps.

 

[midnightg35x 10+ year member]

Another analogy to use is think of water flow. Flowing water also takes the path of least resistance. In the following, the size of the pipe relates to wire gauge, and the amount of water flowing relates to current. If you have a really small water pipe with water flowing through it, you can only X amount of water flowing through it. If you either double the pipe size or add a second pipe, you now have another path for water to flow. In the case of two pipes, half of the water goes into pipe 1 and half goes into pipe 2. This is the exact same idea as adding a second wire of equal gauge size. In the case of a single pipe that was made twice as big, you can still get 2 times the water through it compared to the initial pipe.

This is a simple analogy that does ignore things like thermal effects, but it should get across the point of path of least resistance. Almost everything electrical has a equivalent analogy in mechanics/fluids.